Aging is associated with increasing degrees of both physical and psychological impairment and lowered quality of life. One of the most significant causes of disability and premature death in our rapidly growing elderly population is hypertension, commonly treated with medications that can lower quality of life and may elevate coronary risk. A growing body of epidemiologic and experimental evidence supports the notion that hypertension may be more a modifiable result of disuse than an irreversible aging process, given that: 1) Blood pressure and physical activity levels are inversely related. 2) Only 3% to 28% of the elderly engage in regular physical activity. 3) Aerobic exercise can lower blood pressure (BP) in middle-aged mild hypertensives. 4) It is not known if the physical activities must be of aerobic intensity to lower BP. The present study is designed to evaluate the long-term effects of two intensity levels of exercise in physically inactive, older medicated mild hypertensives. In collaboration with Kaiser Permanente, 150 sedentary men and women, aged 65-85, with mild hypertension will be recruited and randomized to one of three groups: (1) Activity Control, (2) Programmed Aerobic Exercise, and (3) Routine Physical Activities. Treatment will consist of six months of three sessions per week of (1) stretching and minimal physical activities, (2) laboratory-based aerobic walking/jogging/biking, or (3) low intensity, (but isocaloric to aerobic exercise) routine walking and physical activity. Dependent measures obtained at baseline, post-treatment, and 6 and 18 month followup, will include BP and quality of life, fitness, diet, weight/fat, medication use, lipide, urinary electrolytes, depressive symptoms, anxiety and physical activity/exercise adherence. The present project is significant because it will provide the first long- term controlled evaluation of the effects of aerobic exercise vs. low level routine physical activities on BP and quality of life in older hypertensives, while answering the critical question of whether it is the physical activity induced caloric expenditure or the aerobic training effect that accounts for BP reduction to exercise. This study will also provide the first long-term data on the relative effectiveness of two contrasting methods of shaping and maintaining exercise behavior and fitness in elderly patients.